Evaluating Meniscus Lenses using Paper Negatives.
First time users of meniscus lenses are often challenged by the learning curve required to use these lenses effectively.
Interpreting the image on a ground glass and quickly seeing the results in a final print is important in the learning process.
Paper negatives can reduce the "feedback" time between composing on the ground glass and evaluating the lens.
This is only a "quick & dirty" (and cheap) method.
It's not intended to be a treatise on making a "perfect" paper negative.
A series of test exposures takes only a few hours:
-- Use RC paper (any kind).
-- Trim paper to fit the film holder.
-- Expose in camera. (Use ISO ±3~6)
-- Develop. (1+10 stock Dektol, ± 6~8 min)
--15~20 min dry.
-- Scan & invert.
--- or ---
-- Contact print a positive
-- Repeat as necessary.
: Tape a strip of thick paper to your trimmer as a gauge.
(Makes trimming paper to fit a cut film holder easy).
Set lens @ f:32, expose to give a barely visible outline of a coin placed on paper.
: Negatives; Use diluted and/or old print developer, 5~8 minutes.
Aim for a "strong" negative image.
: Examples of evaluating my new 335mm Wollaston lens
Last edited by Reinhold; 03-04-2012 at 01:20 PM. Click to view previous post history.